Jprimus0910

Hi all OK a little update.. I had time to strip my bike a little for a look and it appears my front sprocket had 16 teeth so explains why there's not much get up and go. I bought a 13 tooth sprocket from a 2011 Yamaha YBR 125 as I was struggling to find 1 specific for the YZF but it fits perfect. I Took it out a run and what a difference! Pulls well in every gear. I'm not sure how accurate my speed is now I have 13T/48T setup. I am going to buy a standard 14T sprocket and try that on and update with results. Edit: sprocket that was on my bike was #JTF 417-16 which is from a Kawasaki BN125.

I've felt like that with a few bikes, I'd just like to have more power low down as opposed to top speed for the sake of head winds and overtaking quicker and safely. Also my 6th gear is useless I thought maybe dropping a tooth on the front will increase performance up to 60 mph. A fee people recommend 13t/48t others say 13t/50t. It will make things less of a hassle when I have to tackle hills etc until I get the time and weather for direct access.

Hi everyone, I'm new to this forum and fairly new to biking. Let me tell you a bit about myself, Im 28 years old from Edinburgh. I own a Yamaha YZF R125, best bike iv owned so far. Wish I got into biking sooner as I love every minute of it. First bike I owned was a Honda NSR125, shortly after I went for my CBT which was my first real shot of a bike. I'm looking to go for direct access when and if i can due to work commitments. But fingers crossed we get good weather for it soon

I'll continue to look at pros and cons of sprocket adjustment before i do anything. Thanks for the advice. Sorry yeah I'll post a little introduction. Thanks

Came across this www.gearingcommander.com it shows ratios and speeds not sure how accurate it is but could act as reference point.

Yeah your not kidding there mate hah, i had a read at that topic earlier he appeared to have a tuned bike with quick acceleration, but wanted to reduce it as it seemed to run out of revs in 6th, I get no where near red line in 6th even down hill. Like i say it can sit at 74 n not climb so im lead to believe it is limited (not that im bothered). I'll give youtube a little search aswell but if changing the sprocket means seriously compromise reliability i will give it a miss. Thanks

Yeah very true thanks for advice, just wondered if anyone had personal experience in changing sprocket to increase acceleration without compromising reliability too much. Oh and my daily commute home involves quite a few hills. I have got the patients to put up with it, just frustrating getting passed by HGV's! The bike is really good loads of good reviews which persuaded me to go for the YZF. I really want to get through my test as i love biking, given the choice to use car or bike to work I'd choose bike all day long but like I say weather is always a big downside.

Thanks for reply, i completely understand. thing is i'm not looking for more than 74mph dont care much for doing more than that as it seems to be capped. Sorry my first post may have been misleading and making out as if i want to do 100+. I am just looking for a bit more acceleration. I like the reliability and the economy which is the main purpose for this bike and pretty much every 125 on the market, its basicly a learning curve but too many people try push them past the limitations of the engine and like you say end up blowing them up quick. Does sound stupid yes I should go for bigger bike and save money rather than spending loads on small so called improvements to speed while sacrificing reliability. Little background on myself im 28 5ft 10 at just under 11 stone, my daily 30 mile commute to work consists of dual carriageways with quite alot of head wind and struggle to keep bike up to 50 without dropping gears frantically. Yes big bike would be ideal i have only been biking for a little over a year but the weather in scotland is NOT great, struggle to get half decent weather for biking. I have done my theory and had lessons on a yamaha rn6 while on holiday from my work. I work 6 days a week and cant get lessons on weekends not many riding schools that does evenings unfortunately, so i thought a bit better acceleration would help make head winds a little easier. If that makes sense ? Thanks

Hi all im new to the forum, i have done quite alot of searching online and haven't found what im looking for so hear am I. Ok I have looked around and seen people saying they get 80+ out of the bike I understand 4 strokes are not restricted physically, but are they restricted electronically ? The reason I ask is I was travelling down hill tucked in, my speedo went to 75 then back to 74 and wouldn't budge as i was still going down hill and wasn't on rev limiter ? My other question is it would be nice to get a bit more acceleration out of the bike for overtaking purposes. Could I change either sprocket to gain acceleration ? I know if you gain acceleration you lose top speed but 'if' its restricted electronically to 74 I'm not too concerned about top speed. Any help would be great thanks